PROGRAMS - SUMMER 2014

Deadline for Applications is January 31

* denotes the organizer responsible for participant diversity in the workshop

Physicists are encouraged to apply as individual researchers to work on their own projects at the Aspen Center for
Physics for up to five weeks at any time during the summer. We provide a serene atmosphere to complete work. The individual researcher may also choose to
attend any workshop meetings or chat with other scientists in residence in addition to working on his or her own research.
Click here for more information.

Working groups of between two and six physicists are encouraged. Click here for more information.

May 25 - June 15 Dwarf Galaxies as Cosmological Probes Organizers:Elena D'Onghia, University of WisconsinMike Boylan-Kolchin, University of Maryland Alyson Brooks, Rutgers University Marla C. Geha, Yale University Julio Navarro, University of VictoriaBeth Willman, Haverford College

Recent wide-field surveys have revolutionized our understanding of the Local
Group of Galaxies. The Sloan Digital Sky Survey, in particular, has more than
doubled the number of known dwarf galaxies orbiting the Milky Way and revealed
a new population of ultrafaint dwarf satellites. At the same time, advances
in computational cosmology have led to improved predictions for the properties
of the smallest dark matter halos that host dwarf galaxies in the current
paradigm of structure formation, the Lambda Cold Dark Matter model.

The simultaneous progress in the modeling and observing fronts has transformed
dwarf galaxy studies into powerful probes of both the prevailing cosmological
paradigm and of our understanding of galaxy formation. Locally, dwarfs trace
the extreme faint end of the galaxy formation process, while at high redshift
they seem to play an important role in the reionization of the Universe.
Making explicit connections between the high and low redshift Universe holds
the promise of validating or challenging the current cosmological paradigm of
structure formation on small scales.

This Aspen Summer workshop will bring together experts in Galactic astronomy,
cosmology and stellar astrophysics in order to promote collaborative efforts across theoretical,
computational and observational disciplines. By fostering discussionsn and interactions
between theorists and observers, we aim to help to set the scene for the exploitation of
current and future surveys, including GAIA, and the Large Synoptic Survey Telescope.

May 25 - June 22Modern Trends in Quantum MagnetismOrganizers:Andrey Chubukov, University of Wisconsin Roderich Moessner, Oxford University Satoru Nakatsuji University of TokyoNatalia Perkins, University of Wisconsin Oleg Tchernyshyov, Johns Hopkins University

Much of recent progress in modern condensed matter has been stimulated by important advances
in the field of quantum magnetism. Notable examples of systems in which magnetism plays a crucial role include transition-metal compounds and heavy-fermion intermetallic compounds, where
strong electron correlations lead to emerging collective properties and various novel behaviors. The important role in the understanding of these strongly correlated electron systems is played by
the appearance of new low-energy spin models and development of powerful field theoretical approaches and advanced computational techniques allowing to study these models. This workshop
will provide a broad overview of the latest results in quantum magnetism bringing together experimental and theoretical condensed matter physicists. During the workshop, we plan to discuss a
range of topics including (i) Novel ground states of matter and excitations, (ii) Frustrated magnetism, (iii) Field theories of itinerant magnetism, (iv) Emergent gauge fields, and (v) Interplay of disorder and interactions.

Rapid technical progress and recent discoveries in molecular biology have brought biologists face-to-face with the importance and challenge of understanding emergent physical phenomena in living cells. Nowhere is this more evident than in the study of
bacteria, where fast generation times, tractable genetic systems, a wealth of biochemical probes, novel imaging approaches, and the availability of complete genomes for hundreds of species have allowed dramatic progress in characterizing cellular components and their basic
interactions. However, biologists have found that this characterization is generally inadequate to formulate a full understanding of cellular processes. This “understanding gap” points to the presence in cells of biophysical phenomena, often subtle, complex, and intrinsically out
of equilibrium, that emerge from the multiple interactions of cellular components. Over evolutionary time, cells have exploited and interwoven these biophysical effects to optimize the function of their systems. For physicists, helping biologists to understand how cells use physics
is not only a challenge but also an opportunity: billions of years of “experiments” in biophysics are packed into every cell. This workshop will addressing three broad areas where collaboration between physicists and bacteriologists have and continue to be highly productive:
(1) intracellular organization, dynamics, and mechanics; (2) principles of information transmission and decision making; and (3) principles of nonequilibrium biophysics.

June 8 - June 29Ultra-Compact Binaries as Laboratories for Fundamental PhysicsOrganizers:Paul Groot, Radboud University Nijmegen Ilya Mandel, University of Birmingham Enrico Ramirez-Ruiz, University of California, Santa Cruz Stephan Rosswog,Stockholm University

Ultra-compact binaries with orbital periods shorter than one hour are central to understanding such disparate phenomena as type Ia supernova and short gamma-ray burst explosions; they serve as laboratories for studying the physics of accretion, which produces the bulk of high-energy radiation in the Universe; and they are spectacular probes of the extreme physics at high energy and high density, being strong gravitational-wave sources. Recent progress in observations of ultra-compact populations ranges from a revolution in the discovery of detached white dwarf binaries to observations of gamma-ray pulsars. The coming decade holds enormous promise for further study of ultra-compact binaries, due to the advent of large wide-field and variability surveys to find new systems, efficient optical and near-IR spectrographs combined with large telescopes to allow detailed characterization of their properties, and the imminent advent of gravitational-wave astronomy, which will allow studying these populations in unprecedented detail.
On the theoretical front, detailed modeling of the evolution of binaries, the onset of mass transfer and the merger process itself relies on further developing relativistic numerical
methods, and combining hydrodynamics with radiation and magnetic interaction. The goal of this workshop is to bring together experts in binary evolution, stellar evolution,
accretion processes,gravitational radiation, and radio, optical and X-ray astronomy in order to promote collaborations between these groups.

June 15 - July 6 Fast and Furious: Understanding Exotic Astrophysical TranscientsOrganizers:Joshua Bloom, University of California, Berkeley Ryan Foley, University of IllinoisSuvi Gezari, University of MarylandDaniel Kasen, University of California, BerkeleyAlicia M. Soderberg, Harvard University

Over the last decade, with the implementation of large, systematic, digital-image supernova searches, astrophysicists have begun to discover many astrophysical transients that do
not fall into the traditional supernova classes. About a dozen new types of “exotic” or “peculiar” transients were found lurking in the shadows. These are observationally diverse
events; some are 100 times fainter than typical supernovae, with durations of a few days instead of weeks (“Fast”), while others are 100 times brighter than typical supernovae and
can last for years (“Furious”). Currently, discovery is outpacing understanding. This workshop aims to bring together researchers with diverse backgrounds and varied expertise to
deepen our physical understanding of the heterogeneity of exotic transients, and to draw connections between classes. By bridging the current gap between data and theory,
participants will have the opportunity to develop new theories and observing strategies, necessary preparations for the coming era of Advanced LIGO and LSST.

June 22- July 20 Connecting Flavor Physics with Naturalness: from Theory to Experiment
Organizers: Roni Harnik, Fermi National Laboratory Gudrun Hiller, Technical University of Dortmund Graham Kribs, University of OregonJure Zupan, University of Cincinnati

The past year has seen remarkable progress in the discovery and in scrutinizing the properties of a particle consistent with a Higgs boson.
Electroweak symmetry breaking appears to be well described by a weakly-coupled sector with properties that are broadly consistent with the Standard Model. From the perspective of flavor physics,
the LHC and Tevatron data provide new clues for flavor physics by measuring how the Higgs couples to fermions. From the perspective of electroweak symmetry breaking and Higgs physics, these
new data provide new clues for the naturalness problem.The aim of the workshop is to bring together experts to study flavor physics, and the origins of flavor, and see what impact this has on the naturalness problem of the Higgs sector and vice versa.
Given the various experiments dedicated to flavor physics that are ongoing or planned, combined with the LHC data on Higgs physics, summer 2014 will prove to be an opportune moment to analyze
the theory/experiment interplay for flavor and naturalness.

General arguments from black hole quantum mechanics suggest that spacetime
must be holographic, emerging from degrees of freedom living on a lower
dimensional space. AdS/CFT and other gauge/gravity dualities have given
concrete examples of this. They provide at least a partial formulation of
quantum gravity subject to special boundary conditions via a dual
description which, intriguingly, makes no reference to the usual spacetime
geometry.
Many interesting results follow from this duality, including geometric
realizations of supersymmetry breaking and confinement, new methods for
finite density transport calculations, and the unitarity of black hole
evaporation.
But despite over 15 years of research, central questions involving the
duality are still far from understood. These include the particular manner
in which the bulk spacetime emerges from the dual gauge theory, whether the
duality provides a complete and unique definition of the bulk theory, and
how to best describe bulk degrees of freedom far from the boundary --
especially inside the horizons of black holes. This part of the duality
appears particularly important in attempts to generalize it to backgrounds
closer to the spacetime we observe, dominated by a positive cosmological
constant today and with structure apparently seeded by quantum fluctuations
during early universe inflation. Our program will address central problems
on a broad front using a variety of methods including the study of
entanglement entropy and its connection with spacetime geometry, various
approaches to holography for de Sitter and other cosmological spacetimes,
new insights from the black hole information paradox, and detailed analysis
of concrete models such as higher spin gravity and string-theoretic
constructions.

July 20 - August 10 Combining Probes in Cosmological SurveysOrganizers: Sarah Bridle, University of ManchesterScott Dodelson, Fermi National Laboratory Masahiro Takada, Kavli Institute for the Physics and Mathematics of the Universe

The Lambda-dominated Cold Dark Matter paradigm successfully explains
a broad range of cosmological observations including the recent Planck measurement of cosmic microwave
background anisotropies. However, the success is only
phenomenological in that the model requires introducing
new unknown physics in the form of inflation, dark matter and dark energy or modified gravity.
Understanding the nature of this new physics is arguably the most
tantalizing problem in cosmology today. Cosmological observations, such as galaxy surveys
and cosmic microwave background experiments, offer the most promising way of making progress
on these problems. The workshop will focus on learning even more about the new physics by combining
the many probes made possible by these observations.

August 3 - August 31 Model Building in the LHC EraOrganizers:Mu-Chun Chen, University of California, IrvineStuart Raby, Ohio State UniversityMichael Ratz, Technical University, MunichCarlos Wagner, University of Chicago

The workshop will concentrate on the question of Higgs physics, as well as on
models that provide a description of high energy physics phenomena beyond the
one provided by the SM. It will bring together experts working on the various
areas of particle physics model building and phenomenology (extensions of the standard model,
neutrino, grand unified and string model building) to confront the theories
with current experimental data from the LHC and other experiments, such as
direct and indirect dark matter detection experiments, as well as discussing future searches.Present and future data from the LHC and other experiments may discover new
physics beyond the SM and/or allow us to constrain this new physics. It will
also help us to identify viable settings which are consistent with other
requirements, such as those from flavor physics or cosmology. Guidelines for
model building can come from more top--down scenarios such as grand unified
theories, string compactifications and/or models with (warped) extra dimensions.
We aim at a discussion of how to test such ideas at the LHC and other
experiments, and possibly invent new ways of exploring physics beyond the
standard model.

August 10 - September 7 Gauge Fields in Condensed Matter, Ultracold Atoms and BeyondOrganizers:Victor Galitski, University of MarylandArun Paramekanti, University of Toronto Daniel Podolsky, Technion Ian Spielman, National Institute of Standards and Technology Smitha Vishveshwara, University of Illinois

The physics of gauge fields spans energy scales ranging from trillions of Kelvin in particle physics to the scale of a few Kelvin for solids.
Recent experiments on ultracold atomic gases have made remarkable breakthroughs in realizing synthetic magnetic fields and spin-orbit coupling
for neutral atoms, pushing the energy scale to observe the physics of
gauge fields down to the nano-Kelvin. Parallel developments in condensed
matter physics include the discovery of new states of quantum condensed
matter --- topological insulators, quantum spin liquids, and Chern
insulators --- in which spin-orbit coupling and emergent dynamical gauge
fields play an important role. Particles such as the famous Higgs boson,
which play a crucial role in gauge theories of elementary particles and in
condensed matter physics, have also recently been detected in experiments
on the atomic Bose Hubbard model. Such emergent gauge fields also appear
in itinerant magnets, accompanying the formation of exotic skyrmion textures.
The aim of this workshop is to bring together leading theorists and
experimentalists in the field of ultracold atomic gases and condensed
matter physics in order to foster an exchange of ideas. Given the rapid
developments in these areas, both in ultracold atoms and solid-state
physics, such an interdisciplinary workshop would be extremely timely and
have a great impact in setting directions for future research.

Despite the great progress made over the last 50 years in understanding quantum many-body systems in equilibrium, their
dynamics far from equilibrium has remained relatively unexplored until quite recently. This results in part from the fact that we do not yet have a unified theoretical framework for
non-equilibrium systems that is comparable to well-established concepts of universality in equilibrium systems, and in part because it was previously very difficult to probe
nonequilibrium relaxation processes in experiments. This picture has changed rapidly in the last few years as great progress has been made in the AMO and Condensed Matter
communities, both in terms of new experiments that give access to dynamics on fast timescales and in clean environments, and also in terms of theoretical advances in describing
these processes. The goal of this program is to bring together a core of theorists and experimentalists from the AMO and Condensed Matter communities, as well as a variety of
researchers from other fields. We will discuss recent developments in the understanding of many-body quantum dynamics, with an emphasis on the advances in theoretical
formalisms and experimental approaches that have made those developments possible. By stimulating the sharing ideas between these separate communities, and bringing these
communities in contact with researchers studying out-of-equilibrium processes in other subfields, we aim to accelerate the development of an understanding of far from equilibrium quantum dynamics.

August 24 - September 14 The Galaxy-Halo Connection Across Cosmic TimeOrganizers:Andreas Berlind, Vanderbilt UniversityFrank Van Den Bosch, University of UtahJeremy Tinker, New York University Risa Wechsler, Stanford UniversityAndrew Zentner, University of Pittsburgh

August 31 - September 14Radiation Driven Outflows in Stars and QuasarsOrganizers:Janet Drew, University of Hertfordshire Martin Elvis, Harvard-Smithsonian Center for AstrophysicsFred Hamann, University of FloridaNorman Murray, University of TorontoNolan R. Walborn, Space Telescope Science Institute

Radiation pressure operates in a wide range of astrophysical environments from comets to quasars. Both the phenomenology and the physics
involved is complex and is dominated by electron scattering and atomic line driving in ionized environments. Understanding line driving and closely associated problems are subjects of active interest
in several distinct fields. This workshop concentrates on the best-studied areas: stellar winds in hot stars and disk winds in compact binaries, and quasars. These separate fields are a classic case of
long-suspected, but little-explored physical commonalities. For example, understanding of O-star wind physics is quite advanced, while that of quasars is less so and might benefit from the former.
Conversely, quasar phenomena span a wider range of physical conditions and so may well illuminate the key physics to apply to current issues in massive stellar winds. By bringing the best observers
and theorists in each field for extensive discussions this workshop aims to establish collaborations across research areas. To enable this no session will be exclusively focused on stars, CVs or on
quasars, but will address a single physical problem common to both.

* Organizer in charge of Diversity
For more information about the Aspen Center for Physics, call (970) 925-2585 or email acp at aspenphys. org.